de Sá Sandra Valéria, Corrêa-Giannella Maria Lúcia, Machado Márcio Carlos, Krogh Karin, de Almeida Madson Queiroz, Albergaria Pereira Maria Adelaide, Coelho Siqueira Sheila Aparecida, Patzina Rosely Antunes, Ibuki Felícia Satie, Sogayar Mari Cleide, Machado Marcel Cerqueira César, Giannella-Neto Daniel
Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Sao Paulo, Brazil.
Clin Cancer Res. 2007 Sep 15;13(18 Pt 1):5322-30. doi: 10.1158/1078-0432.CCR-06-1477. Epub 2007 Sep 12.
The biological behavior of insulinomas cannot be predicted based on histopathologic criteria in which the diagnosis of malignancy is confirmed by the presence of metastases. In this study, microarray and quantitative real-time reverse transcription-PCR were applied to identify differentially expressed genes between malignant and nonmalignant insulinomas to search for useful biomarkers to recognize the metastatic potential of insulinomas.
Code Link human bioarrays were used to analyze differences in approximately 20,000 genes between six well-differentiated endocrine tumors of benign behavior compared with one well-differentiated endocrine carcinoma (WDEC) and three metastases of endocrine carcinomas (MEC). Quantitative real-time reverse transcription-PCR was used to validate differential expressions of five genes in a series of 35 sporadic insulinomas. Serpin peptidase inhibitor clade A member 1 (SERPINA1; alpha-1-antitrypsin) expression, identified as up-regulated in malignant insulinomas, was also evaluated by immunohistochemistry.
Analysis of microarray data resulted in 230 differentially expressed genes. Gene Ontology analysis identified serine-type endopeptidase activity and serine-type endopeptidase inhibitor activity as pathways presenting significant differential expression. Protease serine 2 and complement factor B (from serine-type endopeptidase activity pathway) were respectively confirmed as up-regulated in well-differentiated endocrine tumors of benign behavior (WDET) and in WDEC/MEC. Angiotensinogen and SERPINA1 (from serine-type endopeptidase inhibitor activity pathway) were confirmed as up-regulated in WDEC/MEC. SERPINA1 was shown to be expressed in 85.7% of malignant versus 14.3% of nonmalignant insulinomas by immunohistochemistry.
Our data are consistent to the possibility that SERPINA1 is a marker of malignancy in insulinomas. Given the widespread availability of antibody anti-alpha-1-antitrypsin in pathology services, SERPINA1 expression evaluation might be of clinical utility in recognizing patients more likely to develop an aggressive presentation.
胰岛素瘤的生物学行为无法基于组织病理学标准进行预测，在该标准中，恶性肿瘤的诊断通过转移的存在来确认。在本研究中，应用微阵列和定量实时逆转录聚合酶链反应来鉴定恶性和非恶性胰岛素瘤之间差异表达的基因，以寻找有助于识别胰岛素瘤转移潜能的生物标志物。
使用编码链接人类生物阵列分析6个行为良性的高分化内分泌肿瘤与1个高分化内分泌癌（WDEC）和3个内分泌癌转移灶（MEC）之间约20,000个基因的差异。定量实时逆转录聚合酶链反应用于验证35例散发性胰岛素瘤中5个基因的差异表达。丝氨酸蛋白酶抑制剂A家族成员1（SERPINA1；α-1抗胰蛋白酶）的表达在恶性胰岛素瘤中被鉴定为上调，也通过免疫组织化学进行了评估。
微阵列数据分析产生了230个差异表达基因。基因本体分析确定丝氨酸型内肽酶活性和丝氨酸型内肽酶抑制剂活性为呈现显著差异表达的途径。蛋白酶丝氨酸2和补体因子B（来自丝氨酸型内肽酶活性途径）分别在行为良性的高分化内分泌肿瘤（WDET）和WDEC/MEC中被确认为上调。血管紧张素原和SERPINA1（来自丝氨酸型内肽酶抑制剂活性途径）在WDEC/MEC中被确认为上调。免疫组织化学显示，SERPINA1在85.7%的恶性胰岛素瘤中表达，而在非恶性胰岛素瘤中为14.3%。
我们的数据与SERPINA1是胰岛素瘤恶性肿瘤标志物的可能性一致。鉴于病理服务中抗α-1抗胰蛋白酶抗体广泛可用，SERPINA1表达评估可能在识别更可能出现侵袭性表现的患者方面具有临床实用性。
